Replace identifiers related to clipping DNS ttls.

This is an automated commit, generated by this command:

./scripts/maint/rename_c_identifier.py \
        MIN_DNS_TTL_AT_EXIT MIN_DNS_TTL \
        MAX_DNS_TTL_AT_EXIT MAX_DNS_TTL \
        dns_clip_ttl clip_dns_ttl

src/core/or/connection_edge.c

@@ -480,7 +480,7 @@ connection_edge_end(edge_connection_t *conn, uint8_t reason)
       memcpy(payload+1, tor_addr_to_in6_addr8(&conn->base_.addr), 16);
       addrlen = 16;
     }
-    set_uint32(payload+1+addrlen, htonl(dns_clip_ttl(conn->address_ttl)));
+    set_uint32(payload+1+addrlen, htonl(clip_dns_ttl(conn->address_ttl)));
     payload_len += 4+addrlen;
   }
 
@@ -845,7 +845,7 @@ connected_cell_format_payload(uint8_t *payload_out,
     return -1;
   }
 
-  set_uint32(payload_out + connected_payload_len, htonl(dns_clip_ttl(ttl)));
+  set_uint32(payload_out + connected_payload_len, htonl(clip_dns_ttl(ttl)));
   connected_payload_len += 4;
 
   tor_assert(connected_payload_len <= MAX_CONNECTED_CELL_PAYLOAD_LEN);

src/feature/client/addressmap.c

@@ -689,7 +689,7 @@ client_dns_set_addressmap_impl(entry_connection_t *for_conn,
   if (ttl<0)
     ttl = DEFAULT_DNS_TTL;
   else
-    ttl = dns_clip_ttl(ttl);
+    ttl = clip_dns_ttl(ttl);
 
   if (exitname) {
     /* XXXX fails to ever get attempts to get an exit address of

src/feature/relay/dns.c

@@ -272,16 +272,16 @@ has_dns_init_failed(void)
  * OP that asked us to resolve it, and how long to cache that record
  * ourselves. */
 uint32_t
-dns_clip_ttl(uint32_t ttl)
+clip_dns_ttl(uint32_t ttl)
 {
   /* This logic is a defense against "DefectTor" DNS-based traffic
    * confirmation attacks, as in https://nymity.ch/tor-dns/tor-dns.pdf .
    * We only give two values: a "low" value and a "high" value.
    */
-  if (ttl < MIN_DNS_TTL_AT_EXIT)
-    return MIN_DNS_TTL_AT_EXIT;
+  if (ttl < MIN_DNS_TTL)
+    return MIN_DNS_TTL;
   else
-    return MAX_DNS_TTL_AT_EXIT;
+    return MAX_DNS_TTL;
 }
 
 /** Helper: free storage held by an entry in the DNS cache. */
@@ -521,7 +521,7 @@ send_resolved_cell,(edge_connection_t *conn, uint8_t answer_type,
   uint32_t ttl;
 
   buf[0] = answer_type;
-  ttl = dns_clip_ttl(conn->address_ttl);
+  ttl = clip_dns_ttl(conn->address_ttl);
 
   switch (answer_type)
     {
@@ -593,7 +593,7 @@ send_resolved_hostname_cell,(edge_connection_t *conn,
   size_t namelen = strlen(hostname);
 
   tor_assert(namelen < 256);
-  ttl = dns_clip_ttl(conn->address_ttl);
+  ttl = clip_dns_ttl(conn->address_ttl);
 
   buf[0] = RESOLVED_TYPE_HOSTNAME;
   buf[1] = (uint8_t)namelen;
@@ -1338,7 +1338,7 @@ make_pending_resolve_cached(cached_resolve_t *resolve)
         resolve->ttl_hostname < ttl)
       ttl = resolve->ttl_hostname;
 
-    set_expiry(new_resolve, time(NULL) + dns_clip_ttl(ttl));
+    set_expiry(new_resolve, time(NULL) + clip_dns_ttl(ttl));
   }
 
   assert_cache_ok();
@@ -2188,7 +2188,7 @@ dns_cache_handle_oom(time_t now, size_t min_remove_bytes)
     total_bytes_removed += bytes_removed;
 
     /* Increase time_inc by a reasonable fraction. */
-    time_inc += (MAX_DNS_TTL_AT_EXIT / 4);
+    time_inc += (MAX_DNS_TTL / 4);
   } while (total_bytes_removed < min_remove_bytes);
 
   return total_bytes_removed;

src/feature/relay/dns.h

@@ -13,9 +13,9 @@
 #define TOR_DNS_H
 
 /** Lowest value for DNS ttl that a server will give. */
-#define MIN_DNS_TTL_AT_EXIT (5*60)
+#define MIN_DNS_TTL (5*60)
 /** Highest value for DNS ttl that a server will give. */
-#define MAX_DNS_TTL_AT_EXIT (60*60)
+#define MAX_DNS_TTL (60*60)
 
 /** How long do we keep DNS cache entries before purging them (regardless of
  * their TTL)? */
@@ -27,7 +27,7 @@
 int dns_init(void);
 int has_dns_init_failed(void);
 void dns_free_all(void);
-uint32_t dns_clip_ttl(uint32_t ttl);
+uint32_t clip_dns_ttl(uint32_t ttl);
 int dns_reset(void);
 void connection_dns_remove(edge_connection_t *conn);
 void assert_connection_edge_not_dns_pending(edge_connection_t *conn);

src/test/test_dns.c

@@ -80,11 +80,11 @@ test_dns_clip_ttl(void *arg)
 {
   (void)arg;
 
-  uint32_t ttl_mid = MIN_DNS_TTL_AT_EXIT / 2 + MAX_DNS_TTL_AT_EXIT / 2;
+  uint32_t ttl_mid = MIN_DNS_TTL / 2 + MAX_DNS_TTL / 2;
 
-  tt_int_op(dns_clip_ttl(MIN_DNS_TTL_AT_EXIT - 1),OP_EQ,MIN_DNS_TTL_AT_EXIT);
-  tt_int_op(dns_clip_ttl(ttl_mid),OP_EQ,MAX_DNS_TTL_AT_EXIT);
-  tt_int_op(dns_clip_ttl(MAX_DNS_TTL_AT_EXIT + 1),OP_EQ,MAX_DNS_TTL_AT_EXIT);
+  tt_int_op(clip_dns_ttl(MIN_DNS_TTL - 1),OP_EQ,MIN_DNS_TTL);
+  tt_int_op(clip_dns_ttl(ttl_mid),OP_EQ,MAX_DNS_TTL);
+  tt_int_op(clip_dns_ttl(MAX_DNS_TTL + 1),OP_EQ,MAX_DNS_TTL);
 
   done:
   return;